The present invention relates to a device for processing poultry wings as described in the preamble of the first claim.
In recent years, an increasing consumption has been observed of so-called lollipops, comprising poultry meat trussed up around an end part of a bone, the meat remaining at least partly attached to the bone. The bone functions as a handle when eating the product. These so-called lollipops are most often by processing chicken wings or pinions. To increase production of such lollipops, devices have been developed with which the processing of chicken wings and pinions may be carried out in an automatic manner.
In US-A-5.267.891 a device for processing pinion parts of chicken wings is disclosed, which comprises a rotatable, horizontal table carrying a plurality of holders, each holder being designed for containing a single pinion in a substantially vertical direction. As the table is rotated, one holder after the other comes into alignment with a vertically aligned pusher device, having a head with a frustoconical shape, which is dimensioned so as to receive the head of the bone in it. As the pusher device carries out a downward stroke, the head of the pusher device is pressed against the upper apex of the pinion, following which the pusher device and pinion are displaced through a clamping device which causes the flesh to be trussed up around the head of the pusher device. The conical shape of the central space of the clamping device in which the pinion and pusher device are received in the course of the trussing up operation, assist in shaping the pinion. As the pusher device proceeds in downward direction, the opening of the clamping device is increased in a stepwise manner, until the pusher device passes through a central hole in a flexible membrane positioned below the clamping device. This central hole is dimensioned somewhat smaller than the pinion, and in that way assists in shaping the flesh and in pushing out of the meat ball during the retracting stroke of the pusher device.
Before being processed with the device of US-A30 5.267.891, the wing or pinion are cut open in cross direction of the bone, at a position above the cotyle. It is alleged that following this cutting there is a tendency of the flesh and skin tend to retract towards the apex of the bone to which they remain attached. However, the radius, i.e. the smaller bone within the pinion, needs to be removed by pulling it out before the pinion can be processed in the device of US-A-5.267.891. This is time consuming and involves the risk that part of the bone of the radius remains behind in the meat.
From US-A-5.976.004 a device for producing a partly deboned poultry product is known, according to which the bone of the poultry part is urged from its bottom end and over at least along part of its length through a hole of a stripping disc. Thereto use is made of a stripping module comprising a downwardly displaceable pusher device which contacts a first end of the bone. In view of facilitating the stripping action, the second opposite end of the bone is clamped by a clamping device and turned at its second end with respect to the stripping disc as the stripping tool is moved over the bone and the meat is progressively stripped from the first bone end. Before the stripping tool reaches the second end of the bone, the stripping process is terminated, leaving the meat clinging to the second end of the bone. A second pusher engages the first end of the bone and pushes the stripped bone portion back through the stripping disc. The displacement of the stripping tool is controlled by a block which is slidable over a pair of upright parallel guide bars. The sliding movement of the block is in turn controlled by a cam wheel rotatably mounted to it, the displacement of the cam wheel in turn being controlled by a cam track. According to US-A-5.976.004, a plurality of such meat stripping modules may be arranged in series on a continuous conveyor system. However, as the bone has to be displaced through the stripper twice, the processing speed of the device disclosed in US-A-5.976.004 is limited as it is only capable of processing one single poultry wing at the time.
There is a need to a device with which the trussing up of meat around an end portion of a bone can be carried out in a virtually fully automated and economically feasible manner.